Cholera is a severe epidemic diarrheal disease caused by the gram-negative aquatic bacterium Vibrio cholerae. As is true for most bacterial pathogens, attachment to biotic surfaces such as the exoskeletae of copepods and the intestinal epithelium is critical to survival of V. cholerae. V. cholerae can either attach to surfaces as a monolayer, which is defined by the presence of cell-surface adhesion without interbacterial adhesion, or as a biofilm, which is defined by the presence of cell-surface and interbacterial adhesions. In the previous funding period of this grant, we focused on defining the environmental signals, genetic requirements, and gene transcription profiles that defined the V. cholerae monolayer and biofilm. During the next funding period, we propose to investigate three observations made during the previous funding period. These are (i) monosaccharides are strong inducers of biofilm development and transcription of genes encoding monosaccharide transporters is co-regulated with biofilm exopolysaccharide synthesis gene transcription, (ii) secreted proteins play a role in biofilm matrix formation, and (iii) transcription of a putative undecaprenyl pyrophosphate phosphatase is regulated similarly to that of biofilm exopolysaccharide synthesis genes and is required for biofilm formation. The relevant specific aims for this funding period are: 1) To investigate regulation of surface-associated growth in glucose-rich environments and to define its relevance to survival within the host gastrointestinal tract. 2) To characterize the functions of proteinaceous components of the Vibrio cholerae biofilm matrix. 3) To study the role of an undecaprenyl pyrophosphate phosphatase in V. cholerae biofilm matrix synthesis.